includes potential security problems (newline characters) as well as simple
    non-ASCII characters (including international characters and emoji).

 *  **Call canceling is more reliable.**  We had a bug where a socket being
     connected wasn't being closed when the application used `Call.cancel()`.

 *  **Changing a HttpUrl’s scheme now tracks the default port.** We had a bug

  return tensorflow::unwrap(cancellation_manager)->IsCancelled();
}

bool TFE_CancellationManagerIsCancelling(
    TFE_CancellationManager* cancellation_manager) {
  return tensorflow::unwrap(cancellation_manager)->IsCancelling();
}

TFE_CancellationToken TFE_CancellationManagerGetToken(
    TFE_CancellationManager* cancellation_manager) {
  return tensorflow::unwrap(cancellation_manager)->get_cancellation_token();
}

	}

	if z.SinglePool() {
		return errInvalidArgument
	}

	z.poolMetaMutex.Lock()
	defer z.poolMetaMutex.Unlock()

	fn := z.decommissionCancelers[idx]
	if fn == nil {
		// canceling a decommission before it started return an error.
		return errDecommissionNotStarted
	}

	defer fn() // cancel any active thread.

	if z.poolMeta.DecommissionCancel(idx) {

	}

	notAcceptingNewRequestCh := s.lifecycleSignals.NotAcceptingNewRequest
	drainedCh := s.lifecycleSignals.InFlightRequestsDrained
	// Canceling the parent context does not immediately cancel the HTTP server.
	// We only inherit context values here and deal with cancellation ourselves.
	stopHTTPServerCtx, stopHTTPServer := context.WithCancelCause(context.WithoutCancel(ctx))

			// (Perhaps c.Wait hadn't been called, or perhaps it happened to race with
			// c.ctx being canceled.) Don't inject a needless error.
		} else {
			err = wrappedError{
				prefix: "exec: canceling Cmd",
				err:    interruptErr,
			}
		}
	}
	if c.WaitDelay == 0 {
		resultc <- ctxResult{err: err}
		return
	}

	timer := time.NewTimer(c.WaitDelay)
	select {

			// Panic instead of calling t.Fatal so that we get a goroutine dump.
			// We want to know exactly what the os/exec goroutines got stuck on.
			debug.SetTraceback("system")
			panic("canceling context did not stop program")
		}

		// Back off exponentially (up to 1-second sleeps) to give the OS time to
		// terminate the process.
		delay *= 2
		if delay > 1*time.Second {